This application claims the priority of German Patent Document 100 52 881.3, filed Oct. 20, 2000, the disclosure of which is expressly incorporated by reference herein.
This invention relates to a control device for a gear of a motor vehicle, where the control device sets the speeds or transmissions of the gear according to a control program.
Gears with such a control device are usually referred to as automatic gears. The gears thus used can be based on various designs. Most widespread are so-called step automats that in structural terms have a fixed number of speeds (=transmission steps). Then there are also infinitely variable change-speed gears whose transmission basically can be set freely. German Patent DE 41 20 540 C1 discloses that one can provide transmission in order thus to replicate a multistep reduction gear for infinitely variable change-speed gears.
Regardless of the gear model, one may provide that the gears are operated in an automatic operating mode or in a manual operating mode influenced by the driver. In the automatic operating mode, a control program, running in the control device according to operating parameters of the motor vehicle, automatically selects the gears or transmissions of the gear. In the manual operating mode, on the other hand, the driver via an operating device, such as, for example, a switching lever or a switching rocker placed on the steering wheel, has direct access to the various speeds or transmissions of the gear. In the manual operating mode, however, one can trigger switching operations automatically if, for example, the operating range of the driving motor is left or is a kickdown which is activated. Additionally, certain switching programs can be selected for the automatic operating mode such as, for example, a sports program or a winter program. Such selection possibilities here are referred to as options or parameters to influence the control program.
The object of the invention is to improve the adjustment of options or parameters used to influence the control program.
According to the present invention, a memory is provided in the control device in which the options or parameters to influence the control program are filed in an alterable manner. Connected to the memory is an input device that can access the memory in a writing fashion. It is thus possible via the input device to set or alter options or parameters to influence the control program. An input device is accessible to the driver so that these parameters or options for influencing the control program can at any time, although not necessarily during the current operation of the motor vehicle, be changed. The driver advantageously thus has simple access to the setting of the gear and in this way can adapt the performance of the gear to his personal wishes without having to go to a shop or the like.
The present invention has an on-board computer or a navigation system, possibly also a radio or an air conditioning control device to be used as an input device. By using input resources already present in the motor vehicle, one does not need any additional input devices so that the structural effort is diminished.
According to another aspect of the present an input device is operable via an operating device to select a speed or a transmission of the gear. Such operating device, for example, is a switching lever or preferably a switching rocker placed on the steering wheel. This results in a meaningful operation of the input device because, by using an operating device associated with the gear, one can clearly recognize that the input devicexe2x80x94otherwise needed for other purposesxe2x80x94can be used to influence the control device for the gear.
The connection between the input device and the control device should preferably be accomplished via a data bus, for example, a CAN-Bus. Such a data bus is already provided in modern vehicles so that there is no need for any additional lines to connect the input device with the control device.
Inputs via the input device are permitted only if it has been recognized that the motor vehicle is at a standstill. This is checked by determining whether the driving speed is zero and whether a parking position has been set on the gear. In that way, the driver or a passenger can be prevented from accidentally changing the parameters or options during the ongoing operation of the motor vehicle. In particular, by checking the parking position of the gear, it can be ensured that the motor vehicle is not just in a standstill position due to traffic conditions.
An additional safety against accidental changes in the options or parameters can be achieved by updating of the memory. That is to say, inputs or changes via the input device into the memory, can be considered only if the motor vehicle or a combustion engine driving the gear was started over again. As a result, it is no longer possible during current operation to change the options or parameters and, as a result of the necessary renewed start, the driver can clearly see that this is a continuing interference in the performance of the control device and thus the behavior of the gear.
In particular, the following options or parameters are set:
if the gear is an infinitely variable change-speed gear and if the control program replicates a step gear, then as option, it should be possible to set the type of the replicated gear and/or the number of speeds of that replicated gear. The type of the gear, for example, can be an economy gear (with a maximum speed designed to be long) or a sport gear (maximum speed is attained during the highest gear). The number of speeds of the replicated gear should preferably be between 5 and 10.
the performance should be selectable when a combustion engine driving the gear has reached its upper rpm. Preferably, an automatic switchover of the gear upon reaching the upper rpm limit is possible. This setting is effective only in the operating mode influenced by the driver.
the performance of the gear during the activation of a kickdown switch is be selectable. The following are considered as options to be selected: ineffective; switchback into the smallest speed permissible during current operating conditions; switchback by one gear. When the last-mentioned option is chosen, the kickdown switch performs the same function as an operating device of the gear to trigger a switchback.
By virtue of the adjustability of various options or parameters, one may encounter the following problem: The driver will not recognize which options or parameters have just been chosen. The following measures are proposed for this purpose.
After a predetermined standstill time of the motor vehicle, a predetermined standard set of options or parameters is set. The standstill time, however, is preferably so chosen that this will involve more than a brief interruption in driving. In that way, one can make sure that, if the motor vehicle is placed in operation again, the gear will be in a defined basic state. This basic state, determined in the standard set, should be preferably so chosen that options and parameters are picked that ensure safe operation of the motor vehicle. This means for example, for the abovementioned options:
gear type=six-speed sport gear,
automatic increase upon reaching the upper rpm limit=turned on,
activation of kickdown switch=switchback into the smallest permissible speed.
To be able to use the input device, one must also provide a display device for the options and parameters that have just been formed. It is proposed that such a display device or some other display device independent of the input device is always activated when the motor vehicle is placed in operation in order to make it clear to the driver which options and parameters have been chosen. To provide safety against unintentional startup, a handshake device can be provided to help activate the display options and parameters. If this handshake device is not activated, then one sets a predetermined basic setting for the options and parameters. The handshake device can, in particular, be the operating device for the selection of a speed or a transmission and the activation of the former for handshake purposes must differ from the usual activation to prevent accidental handshake. If, by way of example, switching rockers are provided on the steering wheel as activation device, then for handshake purposes, it is necessary to activate both switching rockers simultaneously.
The following is proposed as a further development of the invention: Several memory areas are provided in the memory and these memory areas can be selected by an additional selection device. These memory areas preferably can be matched up with certain drivers if a motor vehicle already contains a possibility for identifying the driver (coded key, dialing switch or the like). In this way, assuming the driver has been identified, the gear will be operated with the options and parameters chosen by that driver. If the driver is not identified, then the gear will reliably be operated with the options and parameters set in the standard set.
Additional options and parameters can also be provided for the automatic operating mode of the gear. In the case of control devices, where, as revealed, for example, in DE 39 22 051 A1, several sets of matchups of speeds or transmissions of operating parameters are provided (that is to say, several switching identification fields or regulation identification fields), one may, for example, in place of the automatic selection of the set of matchups, optionally provide option that a set of matchups be firmly adjustable through the driver. It is also possible to select a set of matchups usually not provided, that is to say, a special switching program. Such a switching program, for example, can be a winter program or a program for trailer operation.
The display device can also be so fashioned that in case of a deviation from the standard settings, the driver constantly gets a hint, for example, through a control lamp in the instrumentation area.